1. Field of the Invention
The present invention relates to a method and system for secondary recovery of oil by injection of water into injection wells for water flooding of oil bearing formation with the crude oil recovered from the recovery or production well being pumped into a concentric tank separator heated by solar energy for effective separation of gas, oil and water with the gas and oil being discharged to storage or other point of use and the heated water serving as an insulator for the inner tank of the separator and being recirculated back to the injection wells for more effective water flooding.
2. Description of Relevant Art
Secondary oil recovery methods and systems have been employed for a number of years in order to recover a larger percentage of crude oil from the oil bearing strata or formation. One method and system which has been employed is water flooding which basically involves the injecton of water or other flowable medium into an injection well or injection wells spaced from a production or recovery well so that the flooding medium which is pumped into the injection well or injection wells under pressure will cause crude oil in the formation to migrate toward the production well or recovery well thus enabling it to be pumped to storage in a conventional manner. While such methods and systems have operated with some degree of success, in our co-pending application there is disclosed a method and system or apparatus in which at least a portion of the recovered crude oil is heated and injected into the oil formation to provide a greater recovery of crude oil from the formation. The apparatus in the co-pending application includes a device for using solar energy to heat the crude being recirculated into the oil formation. That apparatus and method and the art cited in the co-pending application are incorporated herein by reference thereto.